This Week’s Discoveries | 23 January 2018

First Lecture

Title
Ultrasensitive Ethene Detector Based on a Graphene–Copper(I) Hybrid Material

Speaker
Wangyang Fu (SBC, LIC)
Wangyang is a senior researcher in the Supramolecular & Biomaterials Chemistry (SBC) group at the Leiden Institute of Chemistry (LIC). He was recently selected as one of the “Thousand Talents Program for Distinguished Young Scholars” to conduct his research at the School of Materials Science and Engineering, Tsinghua University, China. Wangyang's major research interests lie within the development of innovative biochemical sensors based on new materials and new concepts, including graphene frequency multipliers, near-neutrality point operation, and high frequency detection. Wangyang has over 10 years of experiences in developing cutting-edge nanoelectronic devices, as in-depth studies of device physics and technologies are indispensable for the development of next generation electronic biosensors with ever-demanding reliability and sensitivity.

Abstract
Ethene is a highly diffusive and relatively unreactive gas that induces ageing responses in plants in concentrations as low as parts per billion (ppb). Monitoring concentrations of ethene is critically important for transport and storage of food crops, necessitating the development of a new generation of ultra-sensitive detectors. Here we show that by functionalizing graphene with copper complexes biologically relevant concentrations of ethene can be detected.

Second Lecture

Title
Food and the environment: evaluating the impact of nationally recommended diets.

Speaker
Paul Behrens ( CML and LUC)
Paul is assistant professor in energy and environmental change at CML and Leiden University College. A physicist by training, he is interested in the ways in which human societies can flourish within environmental constraints such as climate change. Paul’s research focuses predominately on energy and food systems as the main drivers of climate change, and combines large environmental datasets with the economy in order to investigate technical and social mitigation options.

Abstract
It has long been understood that what we eat impacts not only our health, but our environment too. The food system occupies around a third of the global, ice-free land, and accounts for a similar proportion of greenhouse gas emissions. Despite this food-sustainability awareness, almost no national dietary recommendations (NRDs) make mention of sustainability. I will talk about the findings of a recent article in PNAS where we looked at the environmental impacts of NRDs in 37 nations worldwide. We found that despite the lack of focus on sustainability, that it is generally better to follow them in high-income nations as they recommend following a plant-based diet and a reduced intake of calories. In lower-income nations there tends to be fewer plant-based proteins available, and many recommendations suggest increased animal product intake, leading to increased impacts. I will discuss some of the avenues for improvement that could be made in recommendations from an environmental perspective.